Tunneling shield with breasting doors

ABSTRACT

THE SHIELD HAS A TUBULAR SKIN. THE RADIALLY OUTER EDGES OF A PLURALITY OF BREASTING DOORS ARE HINGE CONNECTED TO THE SKIN ADJACENT ITS FORWARD EDGE. EACH DOOR IS EQUIPPED WITH AN INDEPENDENTLY CONTROLLABLE HYDRAULIC ACTUATOR WHICH IS PIVOTALLY CONNECTED AT ITS FORWARD END TO A REARWARD INTERMEDIATE PART OF THE DOOR AND AT ITS REAR END TO A LOCATION ON THE SHIELD SKIN SPACED AXIALLY REARWARDLY OF THE HINGE MEANS. THE DOORS BOTH ALONE AND IN COMBINATION WITH A REARWARDLY INCLINING MINED MATERIAL RAMP SERVE TO SUPPORT THE TUNNEL FACE.

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TUNNELING SHIELD WITH BREASTING DOORS Original Filed Dec. l0, 1968 4Sheets-Sheet L www INVENTOR. TYMAN H. FIKSE AT TQFINE YS ffntecl StatesPatent i 3,613,383 Patented Oct. 19, 1971 Int. Cl. E01g 3/03 U.S. Cl.61--85 9 Claims ABSTRACT OF THE DISCLOSURE The shield has a tubularskin. The radially outer edges of a plurality of breasting doors arehinge connected to the skin adjacent its forward edge. Each door isequipped with an independently controllable hydraulic actuator which ispivotally connected at its forward end to a rearward intermediate partof the door and at its rear end to a location on the shield skin spacedaxially rearwardly of the hinge means. The doors both alone and incombination with a rearwardly inclining mined material ramp serve tosupport the tunnel face.

CROSS-REFERENCE TO RELATED APPLICATION This is a divisional of mycopending application Ser. No. 782,567, Ifiled Dec. 10, 1968, andentitled Tunneling Shield With a Drag Loader.

FIELD OF THE INVENTION This invention relates to breasting doors fortunneling shields.

SUMMARY OF THE INVENTION A plurality of breasting doors are mounted onthe forward upper section of a tubular shield. Each door is generallypie-piece shaped but has a blunt rather than a sharp small end. Thecurvature of the arcuate ends of the doors is made to at least closelymatch the curvature of the shield wall and the arcuate outer ends of thedoors are pivotally connected to the inner surface of the wall. Thedoors together substantially close the upper half of the forward openingin the shield. Preferably the doors are sized so that when they areextended the side edges of adjacent doors substantially contact eachother and there is at least some semblance of mutual bracing at suchedges and structural continuation of the doors. Preferably, rather thanbeing planar the doors are convexly curved on their forward sides andconcavely curved on their rearward sides, so that. there is some degreeof keying together of the doors when they are all exended. Each door isprovided with its own independently controllable thrust ram. One end ofeach ram is pivotally connected to its door at a pivot point that islongitudinally spaced along the door from the hinge which connects thedoor to the shield wall. The opposite end of the ram is pivotallyconnected to the wall at a more rearward position. The pivotal axes aresubstantially perpendicularly related to a radial plane, and the ram ispositioned so that it moves 'within said radial plane as the door isextended and retracted.

When soft ground is encountered and the tunnel face does not standup butrather tends to ow into the shield, the doors are extended so as tosubstantially close olf the upper portion of the entrance into theshield. When the doors are in their breasting position the soft materialwill slope from the lower edges of the two lower doors downwardly andinwardly, preferably to a point of intersection with a rearwardlyinclining ramp.

An important feature of the doors is that they can be quickly moved intoa breasting position. This is quite often necessary because a breakdownof the tunnel face with an inward rush of the material quite oftenhappens without any Warning to the personnel working inside the shield.Although the rams are independently operable, the control systemtherefor may be adapted for also moving all doors at once, so that theycan all be quickly moved together into a breasting position in the eventa sudden and unexpected flow occurs.

Other aspects of the invention are hereinafter described in connectionwith the illustrated embodiment.

BRIEF DESCRIPTION OF THE DRAWING In the drawing like elementdesignations refer to like parts, and:

FIG. l is a view partially in vertical axial section and partially inside elevation of a tunneling machine typifying the present invention,such View showing the machine in an in-use position within a tunnel, andshowing breasting doors in retracted inactive positions;

FIG. 2 is a shortened view similar to FIG. -1, showing the shield in theprocess of being jacked forwardly, showing the hoe portion of theexcavator tool being fused for drawing material rearwardly and up theramp onto the conveyor, and again showing the doors in retractedinactive positions;

FIG. 3 is a front elevational view of the tunneling machine showing thebreasting doors relatively tight together in extended or breastingpositions, with the internal elements of the tunneling machine omittedfor the sake of clarity of illustration;

FIG. 4 is a view similar to FIG. 3, but showing the breasting doors intheir retracted positions, and showing the elevating ramp for the minedmaterial and the frame portions only of the excavating equipment infront elevation;

FIG. 5 is a view partially in horizontal axial section and partially intop plan of the tunneling machine, with portions of some elements cutaway for clarity of illustration of internal parts;

FIG. 6 is a fragmentary side elevational view of one of two attit-udecontrol wings which are embedded in the lower outer side portions of theshield;

FIG. 7 is a sectional view taken substantially along line 7-7 of FIG. 6,and presenting a top plan view of the attitude control wing;

FIG. 8 is a fragmentary vertical section View taken through the upperforward portion of the shield and presenting a side elevational view ofone of the upper breasting doors in its retracted position;

FIG. 9 is an enlarged scale view of the rearward mounting portion of thetool boom, such View being partially in top plan and partially inhorizontal axial section;

FIG. 10 is a fragmentary pictorial View of the forward end portion ofthe boom and the preferred form of d-ual purpose tool carried thereby;and

FIG. ll is a View similar to FIG. 10, but showing a second form of dualpurpose tool.

DESCRIPTION OF THE PREFERRED EMBODIMENT The tunneling shield 10 includesa forward section 12 which may be beveled back from top to bottom asillustrated; an intermediate section 14; and a tail section 16. Theshield 10 is moved forwardly by a plurality of thrust rams 18 havingcylinder portions carried by the intermediate section 14 and rearwardlyextendible pistons which react against a husky ring beam 20.

As is conventional in the tunneling field, the tunnel lining iscontinuously added onto and extended forwardly as the shield is advancedforwardly. The illustrated form of tunnel lining is composed of axiallyspaced girth d ribs or beams 22 and wooden plank lagging 24 bridging thespaces between the beams 22. The ring beam abuts against the forward rib22. After the shield has been shoved forwardly an amount approximatelyequal to the full throw of the thrust rams 18, the thrust rams 18 areretracted, the ring beam 20 is moved forwardly, and a new section oflagging and a new forwardmost girth rib 22 are installed under cover ofthe tail section 16. As should be apparent, the shield 10 serves tosupport the earth formation in the region where excavation is takingplace and the tunnel lining supports the tunnel in its extent rearwardlyof the shield 10.

A boom including power excavator E is provided for both (1) digging ormining the tunnel face 26 and (2) drawing the mined material rearwardlyand up a ramp 28 to be discharged therefrom onto an endless belt typeconveyor 30, or the like, which moves such material rearwardly anddeposits it into mining cars 32 or some other form of material carry-outmeans.

The excavating equipment E includes a main support frame F which is inthe nature of a structural triangle. It includes an upper carriagesupport portion 34 which is secured at its forward end to two sideplaced support ears 36, 38 which depend from an intermediate portion ofthe shield section 14. Carriage support portion 34 is disposed generallyhorizontally and extends from its connection points to the ears 36, 38axially rearwardly through the tail section region 16 and possibly alsointo the region of the tunnel rearwardly of the tail section 16 The rearend of the carriage support portion 38 is supported only by a pair ofside located struts 40, 42. The rear ends of the struts 40, 42 are pinconnected to the carriage support portion 34 and the forward ends ofstruts 40, 42 are pin connected to lower portions of the shieldsintermediate section 14. Thus, the support frame F is structurallyconnected only to the relatively husky intermediate section 14 of theshield 10 and extends through free space both vertically between andrearwardly of the securement points 36, 38, 44, 46.

Referring to FIG. 5 in particular, the carriage support portion 34 isshown to comprise a pair of laterally spaced, parallel, tubular rails48, 50. It is the front end portions 52, 54 of the rails 48, 50 whichare connected to the mounting ears 36, 38. The rear ends of the rails48, are interconnected by a cross frame 56 which includes a box-likecentral extension 58 having its own rear end cross member 60. A carriageis mounted on the rails 48, 50 by a pair of mounting sleeves 62, 64,respectively. The carriage frame comprises a pair of vertical sideplates 66, 68 interconnected by a lateral beam 70. The side plates 66,68 are connected to the mounting sleeves 62, 64, such as by tie members72.

A two-piston thrust ram assembly 74 is interconnected between the crossbeam 70 and the end member 60. Stich assembly 74 comprises an elongatedcylinder 76 supported between its ends by a cross member 78 carryingguide g sleeves 80, 82 at` its opposite ends which surroundingly engagethe tubular rails 48, 50. A rst piston 84 is housed within the forwardportion of cylinder 76 and a second piston 86 is housed in the rearwardportion of cylinder 76. The forward end portion 88 of the piston rod forpiston 84 is connected to the cross beam 70 and the rearwardward end 90of the piston rod for piston 86 is connected to the cross member 60.Fluid supply and vent lines 92, 94 are provided through the cylinderwall on the rod sides of the piston heads 96, 98 and a supply and returnline 100 is provided for delivering fluid into the space between thepiston heads 96, 98. In FIG. 5 the carriage is shown in a rearmost orretracted position. The carriage is moved forwardly or extended bydirecting fluid through line 100 into space 102 while at the same timeremoving uid via lines 92, 94.

Referring now to FIGS. l, 2, 5 and 9, in particular, the excavatingequipment is shown to comprise a boom means supported from the forwardportion of the carriage. More specifically, the boom means is shown tocomprise a r0- 4 tatable tool shaft 104 carrying a mining or excavatingtool T at its forward end. A mounting sleeve 106 surrounds the rearwardportion of shaft 104 and at its rear end is connected to a yoke 108which is pivotally connected to a cross beam 110 for sideways pivotalmovement about an axis 112. The beam 110 is itself mounted for pivotalmovement about a generally horizontal axis 114 (FIG. l).

The pivotal connections providing swinging movement of the boom meansabout both axes 112 and 114 serve to mount the boom means, and hence thetool T carried thereby, for universal movement within the confines ofthe shields forward section 12. In the illustrated embodiment threeindependently controllable hydraulic rams are provided for swinging theboom means. The rst ram 116 is pivotally connected at one of its ends toan upper forward portion of the carriage, for pivotal movement about ahorizontal axis 118. At the opposite end it is connected to a forwardportion of the mounting sleeve 106 for pivotal movement about agenerally horizontally axis 120. Second and third rams 122, 124 areprovided on opposite sides of the boom means. Ram 122 is pivotallyconnected at one end to a forward right side extension of the rotatablebeam 110, for sideways pivotal movement about an axis 126. The oppositeend of ram 122 is pivotally connected to the mounting sleeve 106 forsideways pivotal movement about an axis 128. The rear end of rarn 124 ispivotally connected to an opposite end extension of beam 110, forsideways pivotal movement about an axis 130. The forward end of ram 124is pivotally connected to the sleeve 106 for sideways pivotal movementabout an axis 132. Rams 122, 124 are situated in a common plane with theboom shaft 104, and axes 126, 128, 130, 132 are substantiallyperpendicularly related to such plane As should be evident retraction ofthe piston in one of side rams 122, 124 accompanied by extension of thepiston in the other side ram causes a sideways movement of the boommeans and the excavator tool T. Extension and retraction of the pistonin ram 116 causes vertical movement of the boom means and the tool T.

In preferred form, an operators station 134 is suspended from thecarriage between the side plates 66, 68. The operator sits on a seat 136and has the controls for the rams 116, 122, 124 in front of him.

As earlier mentioned, the tool shaft 104 is rotatable. As shown by FIG.9, it is rotated by a hydraulic motor 136, or the like coupled to therear end of shaft 104 and supported within the open center of the yoke108. The motor 136 may be used to merely rotate or revolve the shaft104, and the tool T, a portion of one revolution7 or to continuouslyrotate the shaft 104 and the tool T. This latter arrangement will behereinafter described in greater detail.

To some extent the hydraulic motor 136 can be used to hold or positionthe shaft 104 and the tool T. However, since some rotary hydraulicmotors have a tendency to creep, a position lock mechanism 138 may beprovided for holding the shaft 104 in one or more set positions. In FIG.9 the lock mechanism 138 is shown to consist of a lever 140 pivotallysupported near its middle at 142. A compression spring 144 is situatedbetween the forward end of the lever 140 and the support sleeve 106. Theopposite end of the lever 140 carries a lock pin 146. The lock pin 146is shown to be pivotally connected to the lever 140 by a pin means 148which extends from pin 146 through a longitudinal slot in lever 140. Theinner end of pin 146 is shown to project through rst an opening insupport sleeve 106 and then into an opening or socket 150 in the shaft104. When it is desired to lock the shaft 104 in position relative tosleeve 106, the pin 146 is set in place. Plural openings 150circumferentially spaced about the shaft 104 may be provided so thatthere is a choice of set positons for the shaft 104 and the tool T. Asshould be evident, the shaft 104 and the mounting sleeve 106 may beeasily decoupled by the user merely depressing the spring end of lever140 until the pin 146 is free of both openings. Once it is out of theopening in sleeve 106 it can be swung to one side until it is againdesired to use the lock mechanism 138.

As shown by FIG. 9, the drive shaft 152 of motor 136 is keyed to acircular rear end member 154 which is bolted to a reduced diameter plugmember 156 constituting a rearward portion of the shaft 104. A radialthrust bearing 158 is interposed between the rear surface of member 154and the support wall 160, and a combination bearing 162 is interposedradially between the plug 156 and the wall of sleeve 106 and axiallybetween the forward surface of butt plate 154 and rear end surfaces ofthe tubular portion of shaft 104 and sleeve 106.

In preferred form, the excavating tool T comprises a pneumatic hammer164 having a point 166 directed generally perpendicularly of the boomshaft 104, and an oppositely directed paddle or hoe portion 168. An airsupply line 170 is provided for leading air into the hammer 166.

As best shown shown by FIGS. 1 and 2, a thrust ram 172 is interconnectedbetween a mounting ear 174 projecting laterally from the shaft 104adjacent where it immerges from sleeve 106, and a mounting ear 176offset towards the hoe portion of the tool T from the point ofconnection of the tool T to the shaft 104. Tool T is pivotally connectedto the forward end of shaft 104 for pivotal movement about a transverseaxis 178. The two ends of thrust rams 172 are pivotally attached totheir support ears 174, 176, respectively, for movement about axes whichare parallel to axis 178. Thrust ram 172 is independently controlled bythe operator. The operator control panel includes a set of controls forthis thrust ram in easy reach of the operator. Thrust rams 116, 122, 124and 172 individually and collectively constitute attitude control meansfor the boom means and the tool T carried thereby.

In operation, the boom means is suitably moved by the operator to placethe point 166 of the digging tool at the spot where it is desired to cutor mine the face material. During operation of the pneumatic hammer thethrust rams 116, 122, 124, 172 are selectively operated to suitablybrace the boom means and resist the reaction forces imposed on it by thereciprocating point 166 as it works on the tunnel face 26.

The shield may be shoved forward by the rams 18 during the miningprocess, or the shield 10 may be intermittently thrust forwardly duringthe periods the tool T is used for drawing the mined material rearwardlyup the ramp 28 and onto the traveling belt 180 of the conveyor 30. Theoperator readies the tool T for this latter function by rotating theshaft 104 from the position it is in for digging into the position shownby FIG. 2. The thrust Irarn 74 is then operated to move the carriagerearwardly, carrying with it the boom means and the tool T. As the toolT moves rearwardly the hoe portion 168 collects mined material in frontof it and moves it rearwardly up the ramp 28. As shown by FIG. 10 thehoe portion 168 may be provided with a pair of rearwardly turned side ns182 dihedrally related to the general plane of the hoe portion 168 forthe purpose of minimizing spillage around the sides of the hoe portion168.

As shown by FIG. 1, the rear portion 1-84 of the conveyor 30 iselevated, and is supported in the elevated position by a travelingsupport 186, preferably in the form of one or more pairs of laterallyspaced support members having wheels 188 at their lower ends which rideon the floor 190, or on tracks therefor. During construction of a tunnelit is common to build a slightly elevated floor 190 in the tunnel so asto provide a flat base surface of substantial width. Muck car tracks 192are secured to the floor 190. These tracks are sectional and arecontinuously extended forwardly in the tunnel as the shield is movedforwardly and the tunnel itself is extended.

According to the invention, the forward end of the conveyor 30 issecured to the shield 10, such as by a cross chain 192 which is securedintermediate its ends to the conveyor frame and at its ends to a loweropposite side portions of the ramp 28. The rear portion of the conveyor30 is supported only by its mobile support 186. Hence, the conveyor 30is coupled in trailer fashion to the shield and is pulled forwardly bythe shield as the shield advances.

The chain type support has the effect of substantially isolating theconveyor 30 from roll movement the shield may experience as it is thrustforwardly. As shown by FIGS. 4, 6 and 7, retractable attitude controlwings 194 are provided on the sides of the shield 10 andmay be operatedto at least partially compensate for shield roll. As shown by FIG. 7,the wings are pivotally mounted at their forward ends, such as by asingle pin 196. A hydraulic ram 198 is interconnected between two pivotpins 200, 202, one carried by a fixed mount 204 secured to the shieldwall and the other carried by the wing 194. An arcuate roll of openings206 may be provided in the rear portion of the wing 92 so as to bemovable over an opening provided in a fixed member 208 secured to theshield wall, so that the wing 194 can be locked into position bydropping a lock pin 210 through one of the openings 206 and the openingin member 208. As shown by FIG. 6, the wings are not horizontal, butrather sloped downwardly from front to rear. This gives them a slightangle of attack so that as the shield is moved forwardly with both wingsextended a lifting force will be opposed on the wings causing the shieldto veer upwardly somewhat. At other times one wing 194 is retracted andthe other alone is used so as to impose an upwardly directed force atonly one side of the shield for correcting roll.

Referring to FIGS. 1, 2 and 5, the intermediate sections 16 of theshield includes a pair of stabilizing and guide rails 210, 212, one oneach side of the shield, These members 210, 212 are substantiallyparallel and are spaced laterally apart from each other and about midwaybetween the top and bottom of the shield. Grooved follower wheels 214,216 are carried by the thrust ring 20 and follow along the upper edgesof the guide tracks 210, 212. The guide tracks 210, 212 and the followerwheels 214,

` 216 serve to stabilize and facilitate movement of the ring A pluralityof breasting doors D are mounted on the forward section 12 of the shield10. Each door is generally pie-piece shaped but has a blunt rather thana sharp small end. The curvature of the arcuate ends of the doors ismade to at least closely match the curvature of the shield wall 12, andthe arcuate outer ends of the doors D are pivotally connected to theinner surface of wall 12. The arrangement shown by FIG. 3 includes fourdoors which together substantially close the upper half of the forwardopening in the shield. Preferably the doors D are sized so that whenthey are extended (FIG. 3) the side edges of adjacent doorssubstantially contact each other and there is at least some semblance ofmutual bracing at such edges and structural continuation of the doors D.Preferably, rather than being planar the doors are convexly curved ontheir forward sides and concavely curved on their rearward sides, sothat there is some degree of keying together of the doors when they areall extended. Each door is provided with its own independentlycontrollable thrust ram R. One end of each ram R is pivotally connectedto its door D at a pivot point P1 that is longitudinally spaced alongthe door D from the hinge H which connects the door to the shield wall12. The opposite end of the ram R is pivotally connected to the wall 12at a more rearward position P2. The pivotal axes are substantiallyperpendicularly related to a radial plane, and the ram R is positionedso that it moves within said radial plane as the door D is extended andretracted.

When soft ground is encountered and the tunnel face does not stand upbut rather tends to flow into the shield the doors D are extended so asto substantially close off the upper portion of the entrance into theshield 10. When the doors are in their breasting position the softmaterial will slope from the lower edges of the two lower doorsdownwardly and inwardly to a point of intersection with the ramp 28,with the angle of repose varying in accordance with the composition andflow characteristics of the material. An important feature of the doorsis that they can be quickly moved into a breasting position. This isquite often necessary because a breakdown of the tunnel face with aninward rush of the material quite often happens without any warning tothe personnel working inside the shield. Although the rams R areindependently operable, the control system therefor should be adaptedfor also moving all doors at once, so that they can all be quickly movedtogether into a breasting position in the event a sudden and unexpectedflow occurs.

The excavating tool T shown by FIG. ll is designed to be continuouslyrotated and to cut into the tunnel face as it is rotated. To facilitatecutting it is shown to comprise a plurality of cutters C. It is alsoshaped so that it can be used in hoe fashion to draw the mined materialup thc ramp and onto the conveyor 30.

The purpose of the illustrated embodiment is to provide an understandingof the invention, The following claims set forth the legal limits of theinvention.

What is claimed is:

1. A tunneling shield comprising a tubular skin portion defining aforwardly directed opening; and

a plurality of breasting doors having radially outer edges closelyadjacent the upper portion of the shield skin, said doors comprisingpanel portions which collectively substantially close the upper portionof the said opening when moved into a substantially edgeby-edgegenerally radial breasting position, hinge means connecting the radiallyouter edge of each door to the shield skin, and a hydraulic actuatorinterconnected between a rearward intermediate portion of each doorpanel and a location on the shield skin spaced axially rearwardly ofsaid hinge means, each said actuator serving to move its door betweensaid breasting position and a retracted position substantially againstthe inner surface of said skin, with each actuator being located betweenits door panel and the shield skin when said panel is in its retractedposition. 2. A tunneling shield according to claim 1, wherein each Saidhydraulic actuator is independently controllable.

3. A tunneling shield according to claim 1, further including a minedmaterial receiving ramp mounted in a Cil lower portion of the shield andinclining upwardly and rearwardly, with said breasting doors being usedto support the upper portion of a slumping tunnel face and the rampserving in conjunction with such doors to hold back inward tlow oftunnel face material capable of holding a repose angle.

4. A tunneling shield according to claim 1, wherein Said upper portionof the shield skin has a forward edge and the hinge means for the doorsare located close to said edge.

S. A tunneling shield according to claim 1, wherein the radially outeredges of the breasting doors closely match the curvature of the upperportion of the shield skin.

6. A tunneling shield according to claim 1, wherein each hydraulicactuator includes means pivotally connecting its forward end to therearward intermediate portion of its door and means pivotally connectingits rear end to the shield skin.

7. A tunneling shield according to claim 1, wherein the tubular skinofthe shield has a forward edge which slopes rearwardly from top tobottom and the hinge means for the doors are located close to said edge.

8. A tunneling shield according to claim 7, wherein cach said hydraulicactuator is independently controllable.

9. A tunneling shield according to claim 1, wherein the doors areconvexly curved on their forward sides and concavely curved on theirrearward sides and are dimensioned so that there is some degree ofkeying together of the doors when they `are extended.

References Cited UNITED STATES PATENTS 1,100,142 6/1914 McDowell 61h851,277,107 8/1918 ORourke 6l-85 1,814,852 7/l93l Proctor 6l85 2,208,6087/1940 Stanley 61--85 2,269,418 1/1942 Anderson 6l-85 3,306,055 2/1967Tabor 61-85 3,404,920 10/1968 Tabor 299-31 3,411,826 ll/l968 Wallers etal 61-84 UX 3,427,813 2/1969 Hayes 61-85 DENNIS L. TAYLOR, PrimaryExaminer U.S. Cl. X.R. 299-31

